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Ukrainian President Volodymyr Zelensky has demanded the West steps up military supplies, saying it wasn't just Ukraine at risk.

"What is the price of this security? This is very specific. These are planes for Ukraine. These are tanks for our state. This is anti-missile defense. This is anti-ship weaponry. This is what our partners have. This is what is covered with dust at their storage facilities," he said.

"Because it cannot be acceptable for everyone on the continent if the Baltic states, Poland, Slovakia and the whole of Eastern Europe are at risk of a clash with the Russian invaders.""

He said Ukraine needed just 1% of Nato's tanks and aircraft.

"We did not ask for more. And we do not ask for more. And we have already been waiting for 31 days!"

Image source, Reuters/Hannah McKay

Children in Ukraine face a dire situation and one in two have had to flee their homes, a Unicef spokesperson has told the BBC.

The western Ukrainian city of Lviv has come under heavy rocket fire and James Elder, who's from the UN children's charity Unicef, says the attacks add to the terror felt by people there.

"I'd been to a hospital where I see women go down, every time there's an air raid siren, carrying two day old babies or women 36 weeks pregnant who are frigid cold", he says.

"Those women are hiding again tonight - terrified, petrified. And so many other people and children."

"You can just see in the faces of families who have been through this in Kyiv, or Khakiv, and thought they were getting a moment's respite. Well the missiles tell a very different story tonight."

Image source, AFP/Getty Images

Earlier we reported that the city of Slavutych, where many of the Chernobyl power plant's workers live, has been taken by Russian forces.

Now the International Atomic Energy Agency (IAEA) has expressed its concern over the welfare of the plant's employees, as there has been no staff rotation at the plant for nearly a week.

The IAEA's director general, Rafael Mariano Grossi, says there are concerns about the ability of staff to regularly rotate and return to their homes to rest.

Earlier this month, Grossi stressed the ability of staff to carry out their tasks without undue pressure is one of "the seven indispensable pillars for nuclear safety".

This is not the only nuclear plant held by the Russians. Zaporizhzhia, the largest nuclear power plant in Europe, is also in the hands of Russian troops.

"For God's sake, this man cannot remain in power," said US President Joe Biden of his Russian counterpart, Vladimir Putin, during a speech in Warsaw earlier.

You can watch a clip of the speech - where Biden condemned Russia's invasion of Ukraine - below.

Image source, Reuters

Russia's oligarchs can continue to do business in Turkey so long as they respect international law, Turkey's Foreign Minister Mevlut Cavusoglu says.

He was asked at the Doha Forum in Qatar if Russian oligarchs facing sanctions from western countries could do business in Turkey.

"Of course, if it is legal; if it is not against international law, I will consider it," he says.

"If it is against international law, that's another story."

Two superyachts belonging to Russian billionaire Roman Abramovich docked in Turkey this week.

Nato member Turkey, which has strong ties with both Russia and Ukraine, hasn't joined western sanctions targeting Moscow's oligarchs.

Hugo Bachega
BBC News, Lviv

Image source, Reuters

First, mid-afternoon, the air raid sirens went off. Then, three powerful explosions, and thick plumes of smoke could be seen from the distance. Hours later, another attack.

It all happened a day after Russia said it was focusing its invasion of Ukraine on the east. Lviv is in the extreme opposite.

And this distance from the worst of Russia’s aggression, where people have been under unrelenting bombing and shelling, turned this city into something like a safe haven. Displaced people, humanitarian workers, volunteers. They are all here.

That perception could be changing. Maryanna Pack, a 39-year-old economist who was near the site of the blast, gives a passionate testimony that may be shared by many. “We’re feeling unprotected. Nobody really cares about what’s happening here,” she says.

“We need more help now. Eastern Ukraine has been completely destroyed. It’s really possible that could happen to Lviv and the west of the country too.”

A nuclear research reactor in Kharkiv, Ukraine's second largest city, has been hit by Russian shelling, according to authorities cited in a Ukrainian news outlet.

The Kyiv Independent said because of constant shelling in the area, in the north east of the country, authorities have been unable to assess the damage to the site.

Russia has been repeatedly criticised for targeting nuclear power plants in Ukraine, such as the Zhaporizhia nuclear plant in the south east.

Though risky, there has so far been no release of radioactive material from this site.

BBC Monitoring
The world through its media

Image source, Reuters

The Russian air strikes on the western Ukrainian city of Lviv today were intended to send a message to US President Joe Biden, mayor Andriy Sadovyy says.

He's been speaking at a joint briefing with the head of the Lviv military civil administration, Maksym Kozytskyy, broadcast on YouTube.

"I think that, with today's strikes, the aggressor is sending greetings to President Biden, who is in Poland now. Lviv is 70 km away from Poland," Sadovyy says.

"I think the whole world should realise that the threat is extremely serious."

Kozytskyy says the missiles hit two critical infrastructure facilities, one of which was an oil depot in a residential area in Lviv, and another was a military plant also located in a residential area. Each of them was targeted by two missile attacks, he says.

No-one was killed, Kozytskyy adds, but five people sought medical help.

Image source, Reuters

The Kharkiv Music Festival, in Ukraine's second city, has gone ahead, despite relentless shelling by Russia since the start of the war.

Organisers insisted the event must start as scheduled, so musicians have been performing deep underground, on the marble steps of a metro station which serves as a huge bomb shelter.

A small crowd watched, some with their eyes closed, others holding children or pets, as a string quintet played classical music, as well as the national anthem.

A cello player who performed at the festival, Denys Karachevtsev, said he wanted to deliver a message of hope to the people of Kharkiv:

"My message is that we have no fear, we are strong, and we can be helpful for our country, each person [in their own way]."

Violinist Tatiana Choukh said "it was maybe the best concert of my life".

Image source, Getty Images

The mayor of Ukraine's capital Kyiv - former professional boxer Vitali Klitschko - has urged thousands of protesters in central London to stand with Ukraine.

A huge crowd of people, including Ukrainians living in the UK, politicians and celebrities, marched through London in solidarity with Ukraine.

Klitschko, speaking via video link from a military bunker, told the crowd on a big screen near Nelson's Column in Trafalgar Square: "We defend, right now, the same principles.

"Please keep together with our country, keep together with Ukraine."

Image source, EPA

London mayor Sadiq Khan has announced more than £1.1m in funding to support migrants, refugees and people seeking asylum in the UK capital, and said he was "full of admiration" for people who have offered Ukrainian refugees somewhere to stay.

Ukraine's ambassador to the UK, Vadym Prystaiko, told the crowd: "I urge you to keep up the good work, the military and humanitarian aid.

"The sanctions must continue until the Russian economy has stopped in its tracks."

Image source, Getty Images

Image source, Reuters

It is not for Joe Biden to decide if Vladimir Putin stays in power, the Kremlin says.

As we reported earlier, the US president gave a speech with comments aimed directly at the Russian people, closing with: "For God's sake, this man cannot remain in power."

According to Reuters, a Kremlin spokesman responded: "That's not for Biden to decide. The president of Russia is elected by Russians."

A White House official says Biden was not calling for regime change, but making the point Putin cannot be allowed to exercise power over his neighbours or the region.

Biden was delivering the speech earlier in Warsaw, where he has met Ukrainian government ministers and refugees who have crossed the border into Poland.

BBC Monitoring
The world through its media

Image source, EPA

Russia has destroyed about 4,500 residential buildings, 100 enterprises, 400 educational institutions and 150 medical establishments in Ukraine, a Ukrainian government minister says.

The total damage across the country will be assessed after the end of hostilities and removal of mines, Minister for Community and Territorial Development Oleksiy Chernyshov says, as quoted by the Interfax-Ukraine news agency.

According to preliminary assessments, the losses incurred by Ukraine have reached tens of billions of US dollars, with the sum increasing daily.

With a view to reconstruction efforts, the government has simplified procedures for construction material imports. However, the minister adds, any reconstruction must be preceded by clearing mines and rubble.

Ukraine hopes to involve domestic and foreign specialists in reconstruction efforts.

Hugo Bachega
BBC News, Lviv

Image source, Reuters

The deputy mayor of the besieged Ukrainian city of Mariupol says people are starting to die from starvation and dehydration, as food and water supplies run low and no humanitarian aid is allowed in.

“Some are dying from dehydration and lack of food. Some are dying from lack of medicine, insulin... Because people cannot find medical help,” Sergey Orlov tells the BBC.

“Some mothers do not have milk, and they don't have food for children. What should they do with their infants? I don’t know. There’s no food for children at all in the city.”

Mariupol has been under relentless Russian attacks since the early days of the war, and pictures show a city in ruins, with entire neighbourhoods destroyed. Orlov says 70% of hospitals in the city have been “destroyed by bombing and shelling”.

Communication with the city is difficult, as the phone network is intermittent, so it is hard to independently verify information. Residents spend most of their time in shelters or basements with no electricity, running water, or gas.

“People are just looking for any possibility to survive. [They] share food, water, they’re collecting wood to cook in the street,” Orlov says.

More than 100,000 people remain trapped in Mariupol. Efforts to carry out large-scale evacuations have failed, although thousands have managed to leave in recent days in private vehicles.

Image source, EPA

Next, Joe Biden addresses the Russian people, saying he's worked with Russian leaders for decades, since the height of the Cold War.

"I've always spoken directly and honestly to you the Russian people," he says.

"Let me say this, if you're able to listen. You the Russian people are not our enemy.

"I refuse to believe you welcome the killing of innocent children and grandparents.

"Or that you accept hospitals, schools, maternity wards for God's sake, being pummelled with Russian missiles and bombs.

"Or cities being surrounded so that civilians cannot flee, supplies cut off and attempting to starve Ukrainians into submission.

"Millions of families are being driven from their homes, including half of all Ukraine's children.

"These are not the actions of a great nation."

He closes his speech with a reference to Vladimir Putin - "For God's sake, this man cannot remain in power."

Image source, Reuters

"My message to the people of Ukraine... we stand with you, period," President Biden says during his speech in Warsaw, a line greeted by cheers.

"Today's fighting in Kyiv, Mariupol and Kharkiv are the latest battles in a long struggle," he says.

"Hungary in 1956, Poland in 1956 and then again in 1981, Czechoslovakia in 1968 - Soviet tanks crushed democratic uprisings but the resistance continued until finally in 1989, the Berlin Wall and all the walls of Soviet domination, they fell and the people prevailed.

"The battle for democracy could not conclude and did not conclude with the end of the Cold War.

"Over the last 30 years the forces of autocracy have revived all across the globe. Its hallmarks are familiar ones. Contempt for the rule of law, contempt for democratic freedom, contempt for the truth itself.

"Today, Russia has strangled democracy and has sought to do so elsewhere."

Biden says it is obscene that Vladimir Putin has lied by saying he is trying to de-Nazify Ukraine.

US President Joe Biden says Ukraine and its people are "fighting to save their nation", as he addresses crowds in Warsaw.

Image source, Reuters

US President Joe Biden is speaking in the Polish capital Warsaw.

Stay with us and we'll bring you the latest from his speech.

Hugo Bachega
BBC News, Lviv

More now on the explosions in Lviv. We've heard from residents there. Volodymyr Kachinsky, 24, was working at a restaurant near the area of the western city hit by rocket strikes on Saturday afternoon.

“I had never heard anything like this. I can only imagine what’s happening in the east.”

He says he still thought Lviv was safe. “[But] it was really scary.”

Maryanna Pack, a 39-year-old economist, was also nearby.

“It was a loud noise,” she said. “We’re feeling unprotected. Nobody really cares about what’s happening here. We need more help now. Eastern Ukraine has been completely destroyed. It’s really possible that could happen to Lviv and the west of the country too.”

She said she felt the war coming closer to this city.

“Things have changed dramatically. We spend a lot of time in shelters,” she said, because of the constant air-raid sirens. “This is creating fear and anger.”

Image source, Reuters

US President Joe Biden has described Vladimir Putin as a butcher, during a meeting with Ukrainian refugees in Poland.

Biden made the comment at a televised event at the national stadium in Warsaw, on a visit to show support for Poland over Russia's invasion of Ukraine, during which he also met members of the Ukrainian government.

A reporter asked the president "You're dealing every day with Vladimir Putin, look at what he's done to these people. What does it make you think?"

"He's a butcher," responded Biden before walking away.

Image source, Reuters

Biden also said each refugee he spoke to had asked him to say a prayer for the safety of their father or brother back home in Ukraine.

Image source, Reuters

In response to the president's comments, a Kremlin spokesman quoted by Russia's TASS news agency said Biden's comment narrows the prospects of mending ties between Washington and Moscow.